The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.
Reverse osmosis systems are used to provide fresh water from brackish or sea water. A membrane is used that restricts the flow of dissolved solids therethrough.
A reverse osmosis system involves pressurizing a solution with an applied pressure greater than an osmotic pressure created by the dissolved salts within the solution. The osmotic pressure is generally proportional to the concentration level of the salt. The approximate osmotic pressure in pounds-per-square-inch is the ratio of the salt mass to water mass times 14,000. A one-percent solution of salt would have an osmotic pressure of about 140 psi. Ocean water typically has a 3.5 percent concentration and an osmotic pressure of 490 psi.
Water extracted from a reverse osmosis system is called permeate. As a given batch of saline solution is processed by the reverse osmosis membrane, the concentration of the solution is increased. At some point, it is no longer practical to recover permeate from the solution. The rejected material is called brine or the reject. Typically, about 50% of recovery of permeate from the original volume of sea water solution reaches the practical limit in standard seawater RO systems.
Reverse osmosis systems typically have several components that are under very high pressures that may exceed 1,000 psi. These components include membrane housings, brine tanks, pumps and interconnecting pipes. Providing reinforced components increases the cost of the reverse osmosis system.